1. Field of the Invention
The invention relates to mop heads for holding removable mops of the type wherein the mops are clamped between relatively movable support members.
2. Description of the Prior Art
Mop heads for holding removable mop heads have been known for a number of years. In general, these mop heads include parallel, relatively movable support members disposed at the end of an elongate handle. Upon displacing the support members toward or away from each other, a mop can be clamped or released. Representative mop heads are disclosed in the following U.S. Pat. Nos.: 44,081; 798,134; 899,437; 1,245,990; 2,305,352; 2,712,144.
The referenced patents disclose that it is known to use a spring to bias a support member in the form of a movable bar relative to the stationary bar in order to clamp the mop in place. The referenced patents also disclose the concept of using prongs on one of the support members to assist in holding the mop in place. The patents to Helminiak, U.S. Pat. No. 2,305,352 and Dunn, U.S. Pat. No. 2,712,144 also disclose that it is known to move a portion of the handle, or a movable element attached to the handle, in order to change mops. Yet additionally, the concept of pivoting a movable support member relative to a stationary support member in order to make it easier to remove a soiled mop is known as shown by the patents to Dunn and Rivers, U.S. Pat. No. 899,437.
Despite the teachings of the prior art, certain problems have not been addressed. One of these problems relates to the size and complexity of the components of the mop head. Typically, springs are used to compress the mop between the relatively movable supports. In order to hold the mop tightly in place, the springs must be quite large and strong. Certain of the prior art devices employ two springs, one at each side of the support members. Desirably, only one spring would be used in order to minimize the number of components, and that spring would be smaller and easier to compress than those disclosed in the prior art.
An additional problem not adequately addressed by the prior art relates to the technique by which soiled mops are removed from the mop head. In those instances where the mop is clamped between two support members which are always maintained parallel to each other, the operator must remove a soiled mop by hand. Also, inserting a fresh mop is more difficult than desired because it must be fitted between the two parallel members. The previously mentioned patents to Rivers and Dunn disclose movable support members which can be moved to a non-parallel position relative to a stationary support member. Presumably the non-parallel support members can enable mops to be changed easier. Unfortunately, Rivers' movable support bar pivots in the same plane in which it opens and closes, and it also includes an elongate leg, both of which contribute to making it still relatively difficult to replace mops. Similarly, the Dunn patent discloses a movable bar which carries the mop and which can be pivoted away from a stationary support member, but the stationary support member must have spring pressure removed from it before the movable bar can be displaced. This feature of the Dunn device makes it relatively difficult to change mops.